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Recommended Practice for Embedded Clay Thin Brick ...
Recommended Practice for Embedded Clay Thin Brick ...
Recommended Practice for Embedded Clay Thin Brick in Precast Concrete
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Good afternoon, welcome to PCI's webinar series. Today's presentation is Recommended Practice for Embedded Clay, Thin Brick, and Precast Concrete. My name is Nicole Clow, Marketing Manager at PCI, and I'll be your moderator for this session. Before I turn the controls over to your presenter for today, I have a few introductory items to note. Earlier today, we sent a reminder email to all registered attendees that included a handout of today's presentation. The handout for this webinar can be found in the handout section of your webinar toolbox pane. If you cannot download the handout, please email PCIMarketing at marketingatpci.org. Please note that all attending lines are muted. The GoToWebinar toolbox has an area for you to raise your hand. If you raise your hand, you will receive a private chat message from me. If you have a question, please type it into the questions pane, where I'll be keeping track of them and will read the questions to the presenter during the Q&A period. Also, a pop-up survey will appear after the webinar ends. Today's presentation will be recorded and uploaded to the PCI eLearning Center. Questions related to specific products or publications will be addressed at the end of the presentation. This presentation is non-CEU and not endorsed by AIA. Learning objectives for today's presentation is introducing recommended practice for embedded clay, thin brick, and precast concrete, PCI RP 152.25, and demonstrating the proactive and reactive actions to be taken when producing precast components with embedded clay, thin brick. Our presenter for today is Randy Wilson, Director of Architectural Precast Systems at PCI. I will now hand the controls over so we can begin our presentation. Thanks, Nicole. Thanks, everybody, for attending today. This document that we've been working on through the Architectural Precast Concrete Committee Thin Brick Task Group has been a labor of love, so to speak, because it does take about a year and a half for us to go from inception to publication. So I want to thank all those that have contributed to this presentation. All those that have contributed to this document. You see all their names on the screens. This group of individuals are a balance of brick manufacturers, form liner providers, and precast concrete producers, along with precast concrete professional members. So it's a good cross-pollinated group of professionals whose input are on this document. So the first thing I want to do is, we want to, this document is in the bookstore. It is live. You can go to PCI's bookstore. You can download it. It's a free PDF. There's a charge for a hard copy. I do recommend a hard copy, not because PCI makes money on it, but just because it's good to have one on your shelf, especially if you're a producer, for it's just easier to reference. It's old school, but it's easier to reference when you have a hard copy. I would also recommend that you get some hard copies to hand out to your architects when you're seeing architects, because it's a lot more professional, I think. But again, I'm old school for this document. So the recommended practice for embedded clay thin brick is the primary purpose of this document is to educate all stakeholders on the process to select a brick product that's compatible with precast and outlines a complete process from selection to final approval. And so today's presentation, what we're going to do is we're going to kind of go through the document with some little bit of additional highlights that aren't in the document to give a little background, because this presentation today is for precast producers. It's for our members. So we'll be able to talk freely, or I'll be able to talk freely. You won't, because you're on mute. But I'll be able to talk freely about this document, because I'm only talking to producers and I'm not trying to sell anything, or I'm not trying to really sugarcoat anything. So I'll try to be as blunt as I can as I go through the process. So this is a first edition. This is the first time this book has been published. It does include a thin brick and form liner selection process. It does talk about pre-production planning, some actions to take. It talks about best production practices as products are being produced in the plant. We did add some really nice appendices. When I say we, I mean the committee, the task group did. We added some nice appendices that'll be very user-friendly. One of it is the PCI specification for embedded clay thin brick. That's the document that's been out since early 2000s and was revised in 2016. And it was revised for this document. Nothing in that has changed in regards to the requirements for the thin brick compressive strength, size requirements, tolerances. All that stuff is the same. It's just been edited and put in this document so it's easy to reference. We also have a thin brick manufacturer certificate of compliance, which I'll talk about in a minute. There is an appendix for a thin brick manufacturer letter of variance. Those two things go together. And again, I'll explain those in detail here in a bit. And then we do have a procedure for measuring dimensional tolerances on thin brick, which is a brand new thing for anybody at PCI. And I think it's really kind of one of the big meat and potatoes of this document. And then the thin brick coursing guide, which is, it's nice because it has some dimensions on there for layout that's very important for detailers. So who will use this document? People who know me know that I came up through precast estimating, sales, and project management. And my dad joke is all problems in precast start in sales. So your sales people should read this document. It should be a mandatory that they read this document so they get an understanding of the importance of selecting the right thin brick in the right form liner and help consult with your customers. Project management and purchasing for sure, because there's a lot of specific details in this document that you should be following for best practices. Production and quality control. What happens when you get the brick in the plant? What are you doing? And what happens if you have a problem? How to use it is to educate the customer. Make sure that anytime a customer, an architect, engineer, construction manager, et cetera, is considering using thin brick, this is a good document to share with them so that you can kind of walk down the path, the bouncing ball of having a successful project. Definitely want to collaborate with your thin brick supplier, whether that is a distributor or a manufacturer, or it's your form liner supplier. You want to make sure that you guys are all on the same page of how to execute the project from brick selection all the way through. And again, the same thing with your form liner supplier. You want to communicate with them using this document so you guys can set the precedent and set the standard of how you're going to build a working relationship with each other. So what's next? Well, today we're going to go through this webinar just, again, producer-specific. Talking to producers, not architects, not engineers, not brick distributors. We are going to have a webinar on May 29th that we're going to invite brick distributors to that webinar. And of course, as a PRECAST member, producer, associate, professional member, we'd love for you to be there also. And this is a little soap boxy, but I'm going to say it anyway. I've had this conversation for the last 40 years. When I sold PRECAST, I was in Eastern Ohio, Western Pennsylvania, and there's about three or four PRECAST salespeople in that territory at that time, but there are probably close to 50 brick distributors in that market. And so they outnumber us a great deal. Since 1990 and today, the brick distributors have done a fabulous job of promoting thin brick in PRECAST. So they really are our partners. Again, that's a little controversial statement. Some people don't believe that, but they really are our partners. And so I think if they're going to go out there and try to sell thin brick in PRECAST, then I think it's good that we communicate to them about trying to put them in our shoes and understand what a PRECAST needs so they can speak consistently and collaboratively with us. Again, very controversial. I think some people are saying, yeah, it's about time. And other people are saying, what the hell are you talking about? That's the direction the Architectural PRECAST Concrete Committee has decided to go down. And then finally in June 25th will be a market-driven webinar. That webinar will be outward to everybody in the world, primarily targeting architects and those people who decide on when and how to use Architectural PRECAST specifically, brick-based Architectural PRECAST. And hopefully we'll be able to convince some to say, hey, you know what? Maybe we shouldn't be using full brick. We should be using thin brick in PRECAST. And that's the goal of that last webinar. So what are the details of the document? Let's get into this thing. First thing is selecting thin brick. So what we're doing is we kind of go through part of this document at the beginning is talking about the selection process. So how does a thin brick typically get selected? Well, it's selected by the architect or the owner. They typically go with what they know, right? They're living in a city or a community that has a red brick. I want a red brick building. I'm in a community that uses a brown brick. I want a brown brick. And what's that brown brick? It's from X, Y, Z producer. What happens if that X, Y, Z brick producer doesn't make a thin brick? Now what happens? That's one of the reasons why we get as producers, again, talking to producers, one of the reasons why we have challenges with brick fitting and form liners because an architect has not been educated on the differences between thin brick, form liners, PRECAST, the process, the requirements, the needs, the challenges. They're not educated on this. So they just pick a brick because that's how they typically pick a full brick. Oh, we'll just go with brick from X, Y, Z producer like we always do. And to them, the decision is made. Over the years, a lot of architects are being educated on this, but they just go with what they know. So they call their brick distributors and say, hey, remember that brown brick we did on that job? We're going to do on this job too. And the brick distributor, quote, unquote, just takes a brick sample, sells the job. And next thing you know, you're stuck with a specification with a brick that doesn't meet our requirements as a PCI producer. They just pick it based on size, color, and what they know. Hopefully that rings true with some of you. Doing webinars is kind of a bummer because I can't see people shaking or nodding their heads or not getting spit balls at me. But there are different types of brick. Architects typically know this. There's a residential brick and there's a commercial brick. If you build a precast plant that's going to build bridge beams, it's pretty hard to build a double T or pretty hard to build an architectural panel out of it. But if you build a brick plant for residential brick, it's difficult to make a commercial brick. So not all brick is the same. Some are designed and built or made for commercial use. Some are made for residential use. So there's different types of brick out there. There's also coated brick or sanded brick where you've got a brick that is the body color is red, but the face of it's orange, or the body color is buff color and the face is red because they do put coatings on brick. So that's a challenge that we have to overcome. There's smooth versus textured brick. That's also something that is something you might want to be looking at when you start looking at a brick. So these are all the things that an architect kind of thinks about. And then you start talking about dimensional tolerances. The manufacturing for brick is by the machinery that they purchase and they utilize being the brick manufacturer and the market they serve. A residential brick has a lot wider size tolerances than a commercial brick. Okay, that affects the wall appearance. It also affects the final, how the product is used, what kind of mortar is used in the brick, et cetera, et cetera. Well, again, none of that's compatible with us. We have to, as precast producers, we need a specific brick, low water absorption. It needs to be cut, ground, or extruded to proper size to fit in the form liners. So selecting the brick is a very important part of this document. And I wanted to give you all a little bit idea, just as I said before, about how we're going to do a webinar about for brick distributors to understand us as producers. We thought it would be good to give you as a precast producer a little bit of insight of what a brick manufacturer or brick distributor understands and how they approach things. So who manufactures a thin brick? Well, there really truly is not a manufacturing facility out there that was made. It was built, constructed just to extrude thin brick. If you go to a brick plant, then it's either there to make brick, full brick, or you go to a tile plant, who's there to make a quarry tile or a porcelain tile or some other tile. And what they've learned over the years is that, hey, we can adapt our equipment to manufacture a thin brick and we can open the door to this precast market and this field applied market using a thin product versus a full product. So that's number one. They've got equipment out there that they've built many, many decades ago that's making a full brick or a tile, and now they're adapting it to thin brick. So the way that they make a thin brick is they either extrude a full brick and cut the face or they extrude like a tile and then they split it. So that's the two different ways they manufacture brick. What's the brick manufacturing products? It's raw materials pulled out of the ground. It's mixed in an extruding machine or a mixer, then it's extruded through an extrusion machine, which is the picture in the center, that big round thing is the head of the extruder. And it extrudes a long column of clay material. That clay material gets cut into shapes. Those shapes get dried, they get fired in a kiln, they get packaged and they get shipped. That's how it works. If it's thin brick, and then thin brick is either cut or separated, and then it can be ground if it need be, and then it's waxed and then it's packaged and it's shipped. So it's full brick and thin brick are pretty much made the same way from the start. It just gets modified as it goes through the extrusion process and the final steps. But the key here is it is mother nature, and mother nature sometimes is very difficult to control. So here you see a full brick manufacturing process. On the far left, you see the big round extruder. That's just a long column of clay that's just continuing running out of the extruder. The material is then cut into the brick pieces, and then those pieces are put on kiln cars and put through the drying and firing process. Because it's extruded face up, that face up part of that brick can now, that can have texture or have coating applied to the top of the piece of material, and that's how brick manufacturers get different coating. Now, to manufacture a thin brick, again, you got a full brick, you can actually have the full brick go through the entire process, and then the face can be cut off. Or instead of extruding a brick shape, they can extrude a tile shape, which you see there in the second picture from the left, and then that piece can be broken apart if you have two pieces of thin brick or four, depends on how it's extruded. And they get broken apart, and then those pieces that are broken are then waxed and packaged. And yes, they can be grounded if the thin brick manufacturer has a grinding operation. So what is a thin brick in regards to the requirements that a brick manufacturer looks at? Well, they look at it from an STM document called C1088, that's the ASTM standard for thin brick. That document was primarily written and approved by brick manufacturers for a thin brick that's going to be field applied, just like you would on a backsplash, or you can do a high rise with field applied. I've done them before, too. So what's the gradation? So all of it becomes graded at some point. There's a lot of other data in this ASTM C1088. I would recommend you go get it and read it. But the pertinent data that's in there for us as precasters is there's different gratings. With thin brick, the grating is either interior or exterior. It's basically how much water absorption that material has. Then it's looked at, graded based on size tolerance. A TBA size tolerance is just any size tolerance. There's no set variance. The next is TBS. A TBS is a standard size tolerance. That's the standard size tolerance that you would see for a full brick, which is typically plus or minus a quarter of an inch. Then you have the TBX, or the select tolerance, which is the tightest size tolerance that a typical brick manufacturer can provide. And again, we're talking about field applied applications where tolerances aren't as important as it is when you put it into a form liner. And then you have the physical properties that go along with the clay material, which is absorption. You have other size considerations like warpage and different defects. But one thing they don't typically talk about a whole lot is corners and the 90 degree part of the corner, which I will talk about, because I know that's a hot topic for a lot of you on the call. So what does ASTM's C1088 say about size tolerances? Well, those select tolerances for a typical size brick, which is the eight inch, six to eight inch, is plus or minus 532nds. And I think I don't have to go too far into this. I made a little chart to kind of compare the TBX, TBS, and the PCI. And when you look at that eight inch typical modular brick, TBX is plus or minus 532nds, which is just shy of a quarter of an inch. The PCI requires a plus zero minus 16. Main reasons because form liners are made out of urethane or plastic, and those have zero size tolerance. So they're dead on. So can you imagine having a brick that's plus or minus a quarter of an inch made by a typical full brick manufacturer and try to make that product fit into a form liner on a consistent basis? Most likely that's not going to happen. It has happened. I've had success with that before, but typically it does not. So where did the plus zero minus 16th of an inch come from? And why is that so important? Before I do that though, hopefully my, there we go. I wanted, I have this slide and I've shown to architects a lot of times because, you know, when you look at it on a tape measure, you look at it on the chart, you're like, oh, what's a quarter of an inch amongst friends. But when you compare a quarter inch to a 16th of an inch on a tape measure, and then you explain to an architect how that extra 16th or an eighth or three eighths or three sixteenths or whatever the dimension is, when that grows across a 30 foot long panel or it grows up a six foot tall panel, as precast producers, we have big, big problems. And this is one of the things that we have to express to the brick distributors is, yeah, we're a little bit short. Yeah, we're a little bit heavy. Does it work with us? It might work for one piece, but it's not gonna work 70 pieces across the face of the panel. Those dimensions grow very quickly. And next thing you know, you've got big problems. So just to kind of look at this ASTM spec and then look compared to PCI specs. PCI specs are no less than a half inch, no more than one inch, face size plus zero minus a 16th of an inch. And the warpage is no more than a 16th of an inch. Out of square is no more than a 16th of an inch. And then the shape or the angle or the corner piece would be a plus or minus one degree. Now people say, where'd the plus zero minus 16th inch come from? Well, it's not a real big secret. It comes from the tile industry. That's the size tolerances for quarry tile type products. And that's about as tight as you're gonna be able to get on a regular basis in a extrusion plant, like a tile plant or even a brick plant. The other things that as far as the PCI spec goes is we wanna have a product that has low water absorption, which makes a lot of sense because you don't want brick popping off the wall. You want the brick to move. You want it to adhere to the precast. You don't want it super low where it doesn't adhere. That's why you have the dovetails in the back. But you don't want high water absorption because then the bricks gonna act like a sponge. It's gonna absorb all the water in the face. It won't have any place to escape. And then you're gonna have some spalling or you could have some delamination. So that 6% is kind of that threshold. You want a product that's rated not to have a lot of rust. You want a product that has a modular rupture. And it's also chemically resistant so it can handle acid and power washing and all that good stuff that we'd like to do with precast panels. But all this stuff is in the specification in the document that's been there since early 2000s, but it is the brick manufacturer's responsibility to do this testing. And the main thing that they need to be doing is they need to be doing a pullout test. For those of you that aren't familiar with the pullout test, the diagram there in the blue box is a small precast concrete panel, four inches of concrete or more, with those few brick in it. And then that middle piece is tested for pullout strength. And that's that 150 PSI tensile bond strength before and after freestall. So what happens is, is you take 10 of those samples, five of them you pull out tests, you average that data, and then it has to be over 150. If it's not over 150, I wouldn't do the freestall part. The other five you put into the freestall process, which takes a few weeks. It's the 300 freestall cycles. And then the pullout test is then repeated. And then that after freestall, that tensile bond strength must be over 150. And that's the test. And that gives you the assurance that the product's going to adhere to precast concrete for the long duration. So I want to give you guys that background. Hopefully that was helpful to all of you, trying to better understand how the brick manufacturing is, how it works, how the brick industry kind of works, and then being able to put yourself into their shoes and kind of understand that gap between what brick people go through and what precast people go through, and how we all can come together. The kumbaya moment, so to speak. So appendix A in the document is that PCI specification re-embedded clay thin brick, which we just reviewed. And then appendix B and appendix C are the certificate of compliance and the letter of variance. What is the certificate of compliance? It is a draft of a letter that you, check main thin brick manufacturer, that the thin brick manufacturer is assuring you that they will meet all their product they're selling you, requirements of this document. Basically of the specification, I should say. If their brick does not meet all the requirements of the specification, then they should be providing you a letter of variance that specifically spells out in detail what part of the PCI specification their product does not meet. So let's say that they have a tumble brick, and they're going to say, it's not going to be plus zero minus 16th, but it won't be any greater than seven and five eighths. You might, as a precast, you go, oh my gosh, that'll never work. Well, it has worked. It's the longer bricks, the ones that give us the most trouble. It could say, they could say, the architect wanted this product, it's going to be a little bit thicker than one inch, and we're just going to cut it from a full brick. So it's going to be inch and three quarter, and the cores are going to be shown, but it's less than 8%, and I've had the testing done. Then if everybody's okay with that, and you're okay with that, that's between you and the architect and the brick supplier. This is a way to make sure that you have that communication between all parties going into the job. And you all have that communication, you understand what the brick is going to be, you understand where it's coming from, the architect knows the risks, you guys know the risks, you can price the job accordingly, you can get the right liner, and everybody walks down the path with the best expectations and results possible. So those are what those are. I think it's highly important that you get this document and you use those two specific appendices on every single project. So to kind of summarize the brick selection process, is that, of course, you want to have the certificate of compliance or the letter of variance, that's number one, but within that, you're going to define the dimensional tolerances of the product, you're going to define the sizes and shape, the product properties, and make sure they did all the testing criteria properly as the specification states, and have those conversations. I always tell architects, color and texture should be a secondary criteria. There is more colors and more textures and more sizes available than ever before. And there's more brick manufacturers that are complying to all these specifications. So there shouldn't be any reason why you can't find a brick or a brick manufacturer that can meet these qualifications or meet these specifications, and give a color and size that an architect wants. And a lot of times when an architect does go down this path, they actually find something that's even better than what they envisioned. And that happens more times than not. So don't be afraid of having these conversations with your architect early on, because a lot of times they just don't know what they don't know, because remember what I just said, they usually go with what they know. And sometimes they don't know what you know. That sounded real professional. Selecting a form liner. I'll go through this relatively quickly, because most of you all have a favored form liner, which is a fantastic approach. Go with what you know. Factors to consider when you're selecting a form liner is how much repetition there is, what the joint profile is gonna look like, what's your schedule and availability of liners, brick size and type, your brick coursing, other projects in your plant. Maybe you got a project in there that maybe that liner is gonna work with the next job. Other projects in your plants are very important, I think, when you start looking at jobs. And then any waste considerations with the liner, because you may have some special sizes, shapes, or fields of brick that needs to be addressed. So form liners can be either multi-use, which is urethane or rubber, or they can be a one-time use, which is a plastic. This document, we do realize that there can be custom liners made. A lot of you do make custom liners. This document is primarily written for you to choose one of these two types of liners. Most of everything in this document does apply to any liner you use, via custom liner, bricks and sticks, whatever you use. But when you specifically talk about the liners portion of this document, it's really talking specifically about these two types of liners. So you should familiarize yourself with these types of liners. It does behoove you to have different liner people to come in and demonstrate how their liners work, see what kind of products, what kind of services, what kind of delivery availabilities they have, so that when you do see a project come through, you know exactly how to bid it. You know exactly which form liner company to call and say, hey, I think this is gonna work for X, Y, Z form liner company, give them a call, let's try that out. So that's always good to have different connections and different means and methods when you bid jobs. One of the things that is very important though is to use the same liner for the samples as you use on the project. This will demonstrate your finished product a lot more realistically, because you are using the same joint profile, you gotta use the same mortar color that you're gonna use on the job. And when you're using the brick that's being used for the job, you start to kind of get a feel for how everything's gonna go together. And that way you don't have any, for example, if you use a rake joint on the sample, and then they want a cove joint on the job, the sample's gonna look slightly different. And then that becomes a communication thing. So now you're gonna have another item to communicate with your customer. And when you get a sample, it's exactly where you're gonna produce it. It avoids problems down the road. So sampling and ordering your thin brick and liner, the document does cover this in great detail. The first thing is you wanna follow all PCI QC manual recommendations. You probably have your own quality control manual in your plant, or you have your own purchasing process in your plant. I would review those to make sure that this document is in alignment with your own processes and modify your own processes based on what you learn from this document. You wanna order all your flat pieces in square foot quantities. So take off the mortar joint. If it's a 10 foot long panel by 20 foot tall, that's 200 square foot of brick. And then that's how you order it. When you have a special shape, like a corner edge cap, or any other type of special shaped brick that's not just a flat brick, you wanna order those primarily in piece quantities. You're like, oh, well, it's linear foot, right? No, it's piece, right? What is it? Well, you probably have to take it off in linear foot, then you have to do a conversion rate with your thin brick manufacturer and say I have 1,000 linear foot of these corners, how many pieces do I order? And then they'll be able to tell you exactly how many pieces to order. When you have, it's a lot easier to count pieces when they arrive in your plant than it is to count linear foots when they're all in boxes. So it's better to switch it to a piece count. You wanna take into some waste quantity considerations and the document does talk about that and I will talk about that here in just a second. So let's talk about sampling your thin brick. When you're sampling thin brick, sample it in a piece of concrete. Do not just take a brick board and say, yeah, that looks good to us, that's the brick we're gonna use. Don't do that because when you put it in a precast panel and you power wash it, sometimes the color does change. Plus the joint is not going to be the same as what a typical brick sample looks like because a typical brick sample is either gonna have no mortar joints, the brick is glued to a board or the mortar joints can be tuck pointed by hand and it's not gonna look like a precast joint. So never, ever, ever sample a thin brick just by a sample board. So cast into the precast concrete. So that helps you determine the color, finish and texture prior to bid hopefully, hopefully, fingers crossed. You wanna include all the sample information in the specification and proposal. So when you bid jobs, again, soapboxing here, playing Daddy Randy here, make sure that you read those specifications and you fully understand what the sampling process is and you go by your own sampling process so that you can make sure that you reduce your risks when it comes to color consistency and how these materials work together. So obviously, the first thing you're gonna do is 12 by 12 sample or a few of them to gain written approval. And then once that's approved, go to a four by four sample with the brick and the liner you're gonna use, gain written approval. And then I would always recommend range samples and then insist on a face-to-face meeting with the approving parties so that you can have that conversation, have the brick distributor there, the brick manufacturer there, whomever else that you think is important and have that conversation on every single job. The number one problem I get, number one question I get in my position at PCI is color consistency. And 99% of the time, the color consistency problems arise is because you built a big building with a 12 by 12 sample and didn't do range samples. So I'll get off my soapbox. Produce a mock-up panel if required by the contract. And then again, insist on a face-to-face meeting for the first few project pieces before continuing on. So if you follow that process, your color, texture, consistency issues, most of them go away. So next thing you wanna do when you start to ordering the thin bricks, specifically got your sample, you got everything written off, now you're gonna order your thin brick. Make sure you have that certificate of conformance or that letter of verification so you can have that conversation before you order the brick or at the time you order the brick if you haven't already had that conversation. You wanna order the brick using the manufacturer's color name, the color texture, and any other specific product code that they provide. It's Color Brown-382 Wire Cut, whatever that full name is. That way you can make sure you kind of confirm the manufacturer's nomenclature so there's no confusion. I've seen that happen. People send brick that's the wrong color because it wasn't properly ordered or the order taker didn't clarify. If it's a blend of colors, specify exact blend percentage. What's a blend of colors? Well, a lot of the brick manufacturers will take color red, color orange, color brown, and mingle them together in their plant. So when you get the box of brick, they have so many of each color in them and then that way you don't have to blend a color, blend different colors of brick as you're putting the brick into the form liner. You need to have a specific blend percentage. 33% of this, 50% of that, 12% of this. You need to have that specific blend percentage. Another reason why you wanna do the sampling. You wanna make sure that all, if you're doing a blend, you wanna make sure that all of the brick has that same sizing because a brick manufacturer is gonna run the red, run the brown, run the orange, and then mingle them together. Well, those raw materials may act a little bit differently in the process, just like precast can act differently based on the dew point of the air. They can act differently. And so you may get one brick that might be a sixteenth of an inch longer than the others, but still be within tolerance and you need to know that. When you order anything like a corner or a face or an edge cap or any kind of non-standard size, include all the face dimensions. Better yet, send a detailed drawing to show exactly what all those dimensions are, including the thickness. Sometimes a brick manufacturer, when they make an edge cap or a corner, they have a thickened edge because that way they can hold the brick's shape during the manufacturing process. That may conflict with your reinforcement. So make sure you have that thickness dimension also, especially when you're dealing with special shapes. So when you order the brick and the quantities, flat, thin bricks are going to be in the square foot of wall covers, caps, and special shapes, order in piece counts. Again, you'll probably be a linear foot and then convert it. When, if you go back to the brick ASTMs and the brick company's disclosures, the brick companies say specifically in their documents, they're allowed 5% chippage in full brick. Guess how much chippage we allow as a precaster? Yeah, I hear you all out there, zero, zero. Okay, so we are communicating that to the brick manufacturers. They know there's going to be zero chippage, zero breakage, but we all know there's going to be some. And we also know there's going to be a lot of cuts. So when you look at your overall design and you've got a typical parking garage, four levels, whatever linear foot around each level, you're probably going to be safe in a standard running bond with anywhere between five and 10% waste, because you're only cutting at the edges and there might be some brick that might be a little bit out of tolerance that you might use for cuts. But for primarily that five to 10% waste, whatever you've historically felt comfortable with really works well. If you start getting into a lot of areas where the brick coursing is interrupted, you may want to raise that percentage a little bit. When you go to special shapes, special shapes, I've seen people order special shapes 100% overage. I need 75 edge caps. Well, they'd order 150. Just because if you have 50 edge caps in one panel, that's the one panel that falls off the truck down the highway. That's the panel that you got to replace 50 edge caps. Well, good luck getting 50 edge caps if there's only 75 on the job. So you got to be smart about the waste factor, especially on the special shapes. Understand the specific bricks acceptable color range. I added this slide because I just kind of reiterate that I know you're not brick experts, you're not supposed to be brick experts, but ordering additional thin brick can result in long lead times if bricks that, and brick may not match in color. Brick manufacturers run in runs. I'm going to run so many pieces of orange and I'm going to have so many pieces of brown and so many pieces of red. If you run out of orange and you got a call that, hey, I need more orange, they might not have that orange anymore. They have to rerun the orange and that color may be a shade off. So I always try to get an architect to pick something that had a natural range, kind of like the center photograph, but there's monochromatic, there's a natural range, which means it's the same color, just have a little bit of range to all the brick when you put it together in a field. And then you got the blend, which is different, two or three different or more different colors of brick in the blend. So this is a great opportunity to have a conversation with an architect that they fully understand that if you want a monochromatic color and it's more important to order that overage so that when you do have to order additional brick, it will match because a lot of times it doesn't match. So talking now, kind of switching gears to ordering form liner, clearly communicate and document the total quantity of form liner required for the project. That quantity should include the area, which is typically square footage, any type of field coursing, any kind of returns, any kind of projections, arches, indentation, stack bond, running bond, whatever you got that needs to all be separated out so the liner manufacturer knows exactly what you're doing. But what's really important is to define this, define what you're doing pictorially. I mean, the ideal situation, if you had five molds and you could just send the mold drawings to them and say, these are my five molds. I know you don't do that in estimating, typically don't do it during estimating, but you're just being able just to take an image, snip an image of the different forms and send it to the form liner company. That gets them an idea of what you're looking for and they can start to help you with quantities, the sizing, the coursing, and also the waste factor. So they're very good. All the form liner companies I've worked with are very, very good about the service they provide in defining exactly what you need. But you really need to clearly communicate and document the total quantity of form liner required for the project. And again, pictorially is the way to go. When you've got a detail like this on the screen and you can kind of highlight what you need, they're gonna be able to price it more accurately and that'll help you out down the road for sure. So when you do order the form liner, it's also recommended to write a thin brick sample to the form liner company and say, so you got the job, you've got an idea how much liner you want, you've had really good communication, now it's time to place the order and move forward. Well, the first step you should make is you should get some of the actual brick for the job, usually a quantity about 25 of the flats and 14 corners of the special shape from the actual thin brick production run, if possible. I know sometimes that that brick hasn't even been made yet when you're ordering the liner, and we understand that. And the form liner people work with all the brick people, so they all have a good communication anyway. But the idea is to make sure, is the best idea is to have that brick in the hand of the form liner before they start to make the liner. And when you have that, then that's the first step. And the other thing is, once you do get the liner in hand, talk to them about what you need to do as far as any kind of a release agent. Do you need release agent? Do you not really need release agent? How that product's going to work with the specific brick that the architect selected. The document moves into the pre-production process about what to do when you receive the brick, when you receive the form liner. You cast your sample and you report your findings. So some bullet points that are all in this document that's really important for you to consider is one is you want to store the brick out of extreme temperatures, ideally indoors. If you don't have an indoor place, outdoors with a cover. If you don't have that, then you want to cover it with something but nothing. You want air to circulate through and you don't want really big black tarps on it because that will melt the wax, especially if you are in any kind of summertime atmosphere. You want to measure a sample set of the brick with calipers. You definitely want to make sure all the brick is there, but you also want to make sure the brick is to size. And when do you want to do that, I ask? Yes, the day it arrives. The sooner you know and the sooner you confirm the brick is within tolerance, the better. And transfer so that the sooner you can find out that you don't believe the brick is in tolerance, the better because it gives you time to respond, react before you get into production. Review the wax coating to ensure that you got adequate coverage. You compare the colors versus the approved color range. Can't do that with wax on it, so you got to make a small sample. So go ahead and make a small sample of some of the brick. Take photos of your inspection process as you're inspecting it, take videos. Again, it's a CYA thing, but it's great to have when you start to communicate with the brick manufacturer because my guess is he's not right down the street. He's states away. So you want to be able to communicate with them of what your findings are. And then you want to follow this procedure for every color and texture received. When you get the form liner in, then you do the same thing. You want to store it out of weather. You want to put the brick in the liner. You want to measure the pockets. You want to do a quick layout. You want to do a dry fit and make sure everything fits. Video, photograph it. And if you see any discrepancies, then you want to make sure that you get people on the phone and get them to your plant and you get that resolved. So you want to report those findings immediately. You want to get everyone all hands on deck if you see a problem because the number one thing, the number one thing the liner people and the brick people understand is you've got to meet your production schedule and you can't be delayed. So they're going to do everything they can to prevent that from happening. So during production, you want to lay out your form liner for the drawings, pretty obviously. Check your coursing dimensions before each pour. For a multi-use, you want to ensure the liner hasn't shrunk or stretched, so you want to do your quality checks once that panel's stripped and the form's clean. You want to do your quality, your dimensional checks. One-time use, you want to ensure an accurate alignment for each day's pour. A lot of times, you can put marks on the side of the mold so you know exactly where your four-foot increments are, or two-foot increments, or whatever is appropriate for your brick coursing. And make sure your brick is in the same spot on the same liner, or the same form, every day, so when two panels are erected side-by-side, those mortar joints line up. So, during production, you want to cut thin brick with a wet tile saw and a non-segmented diamond blade. It is not recommended to use thin brick that is cut in epoxy to make shapes. I know sometimes you're like, oh, I'm out of corners, I'll just cut some thin brick and put them together. That's not recommended at all. You want to make sure that you're using multiple cartons of thin brick from several pallets for each precast panel. You don't just want to bring in one pallet and everybody work off the same one from the top to the bottom. You want to probably have three or four pallets laid out along your beds, and one guy is going to go grab a box from each pallet and then go start placing brick, and then feed each other brick and blend it as you go. And then for, if you are using brick on a vertical surface, like a return, you need to secure that form liner using a form liner manufacturer-recommended procedure. There's all different kinds of ways, and the book actually talks about ways to do that, ways to not do that, and some things to look for as you're producing, and things to look for in quality checks after the panel's been stripped. So you want to make sure you want to continually look at every brick for tolerance as thin brick are being placed in the form liner. You've set aside the non-conforming pieces and use those for cuts, but you want to calculate the percentage as you go. So by the third or fourth day, you can look over and say, those are non-conforming bricks. Well, how many did you put in the forms and how many did you pull out? Is it a 10% overage, 2% overage, or 50% overage? Pretty important to know that number because you can pick up the phone and call the brick manufacturer or your brick distributor and say, hey, I think I'm going to run out of because this is not working for us. But it's better to know that on the third day of the pouring versus the last two days of pouring and say, hey, we're out of brick. Another thing that you want to be looking at during the production process is you want to use protective mats whenever possible, walking on thin bricks, so you can spread the weight over a larger area as you're kneeling on the form and putting things together. Yeah, I've seen people walk on, I've walked on, we've all walked on, but if you don't have, if you have a pebble underneath the brick and it's wobbly, you can break the brick. You also want to inspect for dislodgement before and after rebar replacement, before rebar placement. It's the easiest time to look at things, make sure they're, you know, look at it at an angle, look at it in light. I've seen people use shadow lights to try to get brick, but sometimes brick is not perfectly, some brick manufacturers don't cut brick perfectly thin, so you may have some differential thickness in certain cases. Double check brick coursing, your marks and form liner alignment before casting, those are the marks on the side of your form. When casting, ensure force from the pour of the concrete and the vibration, do not dislodge the thin brick. If you've never done this before, then obviously you want to do some test pours, test your vibration, test your mix design to make sure you get good coverage. I apologize, I'm definitely going to run over a little bit, so, but I think you guys will be okay with that. Production practices, post-production, clean the panels immediately after stripping or as soon as possible after stripping. Inspect that all the wax or retardant has been removed. Scrape the concrete bleed and particles with a non-metallic spatula or a non-metal fiber bristle brush, again, test that method. You definitely don't want to be using a scraper that's going to scrape the brick and damage the brick. Typically, collectively, all the form liner folks have said, hey, if you have 180 degree Fahrenheit water at the panel and you've got about a 1,000 to 1,500 PSI power washer, most likely that wax is going to come off. And there's ways in the manual that talks about how to test that water temperature. So, the hotter the water, the better. If the wax is not coming off, the first thing you want to test is your water temperature. If the water temperature is up and the wax is not coming off, then you probably want to look at your PSI or your nozzle of your power washer, and if that's not, that's all looking good and you've tested everything you can, that's when you call your brick manufacturer and say, here's all the things we tried. What tricks do you have? And they have a few. They have a few. You want to clean from top to bottom and chase the wax down the panel. You want to do about a four to six foot swath, depending on how big your alligator arms are. You just want to kind of work right to the left from top to bottom and chase that wax right off the panel. And you definitely want to protect your thin brick from any post-pore texturing like sandblasting or polishing or acid washing or anything like that that might damage the brick. So, if you've got a brick panel that has part brick, part exposed concrete with a finish on it, you can use plywood as a gasket or a protecting. I've seen people just tape off with a plastic, like just plastic wrap. I've seen them do all kinds of creative ways. I'm sure you all probably would have something, or your folks in your plant would probably have something that's equally proficient for your particular application, but you definitely want to have a strategy when you start getting that wax off. You don't want the wax to go from brick to panel. You want to make sure your panel is protected. So, my advice first, you're going to sandblast to protect your brick. You want to inspect the brick coursing alignment. This is very important. The brick coursing alignment is very important. Probably one of the other things, one of the biggest things I get about brick jobs is that the brick mortar joints don't align from panel A to panel B to panel C to panel D on an elevation. They're off by just a little bit. So once you, when you get a panel out there, start measuring that two foot or four foot module and make sure that those brick coursing align. If they're not aligning, then you'd want to go back in the plant and say, hey, what are we doing? How do we get this? How can we get this form liner to stay where it needs to stay? Brick fit is something you want to look at. You want to get your nose right in there, even though that approval process should be from 20 feet. But you, as the quality control people, need to get your nose right in that joint and make sure that if there's any eyebrows or misalignment brick, or there's anything, tip brick or anything like that, that you see that's excessive, then you definitely want to have a discussion with your production people and see how you can mitigate that. It's a lot less expensive and you have a lot higher quality product. If you communicate with your plant workers and you make the correction in the plant before the panel gets outside. Once it's outside and you got to start digging out brick, it's not fun. Also compare the finished panel with your approved mock-up panel. It sounds simple. It's something you do every day, but you wouldn't believe how many people don't. Because you get flown in a plant and you're like, oh, I'm so busy, I got so much going on. Did you really take the mock-up over and compare it to a few panels? It's very important that you do that as a quality control check, moving through. Appendix D, I think this is a fabulous tool for pre-casters. This is going to be a great way that you're going to be able to communicate to the brick people, especially if you have a brick that comes in that you feel like is not within tolerances. Going back to what I said before, brick comes in, you've got a truckload of brick, you've got 20 pallets of brick. What do I do? Well, the best thing to do is go break into three or five of those. Not pallet one, two, three, four, and five. Pallet one, pallet three, pallet 12, pallet 15. Break in, grab a couple of boxes, and then start measuring brick. If you want to measure using calipers or support of wall, the thousandth of an inch, make a difference. You want to be able to measure bowing, you want to be able to measure length, height, thickness, angles, you want to measure it all. You want to be comfortable, it's your job, it's your risk when it comes to the plant activity. You want to make sure that all this is defined early as possible, and then communicate that back to the brick manufacturer or the brick distributor. How are we measuring brick? This appendix goes through all the standard sizes, and I'll hit a few things here just to kind of better communicate it verbally. Number one is when you measure flats, you're going to measure, we're not measuring bowing at this point, we're measuring just the size. It's the height measurement and length measurement, and you want to measure at those three points across the brick on the height and two on the length. You want to use calipers, don't just want to use a tape measure, that's not accurate enough. You want to use your calipers, and you want to use them in the proper way, and take photographs and videos. Got to look at all kinds of plots on that thickness, same way, you want to measure at the thickest point of the brick, not the valleys of the dovetail or valleys of the ridges on the back, and you want to measure at those eight locations. There will be some variation to that thickness, and there is a tolerance. Usually thickness isn't a big deal with pre-casters, because you're face down in the mold, but when you are face down in the mold, you could have a warped brick. Those are the bricks that you definitely don't want to walk on, because those are the ones that are going to crack on you, but there is a tolerance there, and you want to measure at the center, and that's where you want to use that little wedge tool. You put that bricks on a flat surface, and you can slide the wedge on either side, and that wedge has a measurement on it, and that measurement will tell you if it's within tolerance or not. When you want to measure warpage, these are what I call the frowns or the smiley faces, and when you put them in the mold, you don't want to frown below a smiley, because then it accentuates the bowing, and a lot of times, you might have a piece that bows on one side and is relatively flat on the other, so the drawings that we're showing are pretty consistent with the bowing on both edges, but a lot of times, a brick doesn't bow right in the center, kind of tails on one side or the other, but can't show every condition imaginable, but you want to lay it, put the brick on edge, and then you want to use that wedge to measure that distance between the straight edge and the edge of the brick. If you have a convex warpage, you put the brick face down, and then you can measure each end, so you want to push in the center of that little center arrow, if you can see that underneath the C, you want to push at the center, and then you measure each edge. You don't put your thumb on one end or the other, because that will accentuate, and that's really not the realistic way the brick is going to lay in form. A lot of times, you'll see a brick that's flat from, say, the left edge to three-quarters away towards the right edge, and then that right edge tails up, and again, if you push at the center of the brick, and that tail is up more than the tolerance, then it's out of tolerance, but if you push on that right edge, the left edge will tip up beyond tolerance, and that's not the way to measure the warpage. Same thing here with the warpage is that you just lay a straight edge across from corner to corner, and then you can measure the distance. Again, sometimes that bottom face will be relatively true, and the up face might have a little dip in it or a protrusion in it, and that's how you would measure that. Corners, you want to have a carpenter's square. Ideally, you would have something that is steel or metal or aluminum that's perfectly 90 degrees. You're able to put the brick in there. Actually, this isn't a corner. This is a skewed brick, a skewed thin brick, so you put the thin brick down on the edge of the brick, down on the bottom of that carpenter's square, and then slide it over to the up angle of the up arm of the carpenter's square, and then you measure that distance, and you can measure that distance at the top or the bottom, or you can flip the brick over and measure either way. Now to corners, corners, face flat down on the carpenter's square, slide it to the angle, and if you have an acute angle, then of course you're going to have a measurement at the top. If you have an obtuse angle, then you're going to have that measurement at the bottom. And then what does that measurement need to be? Well, we created a little chart. It's typically about a sixteenth of an inch, which is within that one degree angle. There definitely needs to be some discussion if that angle is a little bit more than a sixteenth of an inch and encroaching an eighth of an inch. It may be workable. It may not be workable. It really depends on the configuration of your project, and exactly the orientation of the thin brick to get that true measurement. But when you're using a micrometer that's able to measure that angle, that's really the best way to do it. But again, if you're, and I'll just make this disclaimer. If you can make it work in your plant, that's the best way to go. The brick may be a little out of tolerance. It might be a little short. It may be a little long. It may be a little bit out of angle. But if you can make it work, that's the best solution, especially if it's not costing you a lot of consternation during the process. Brick is not going to be perfect. Even if somebody meets the PCI specifications, we do have some tolerances in there, but it's really best if we collaborate and work together. Just about done. I apologize for going over, but I think it's important. There is brick coursing guide in this as Appendix E. It's the standard. There's several standard brick courses in the document that we typically use. And the main reason we want to put those in there, because those who detail form liners for precast realize that a 3 8th inch joint is not a 3 8th inch joint. It's not a 3 8th inch joint. Those little 3 8ths variation adds up in a six foot panel, and now you've got the sliver brick. Those dimensions horizontally may not add up. When you say 3 8ths, it really isn't 3 8ths. It's .416 in some of the coursing. So we've identified the different specific coursing for each one of the typical brick courses in a run. So that's why we put that brick coursing guide in there. I didn't have to go through all the brick courses for you. You guys know what that's about. And I wanted to make that point, is those brick coursings in there, because it has the specific dimensions that you can share with the architects. So kind of finishing up with my favorite part of the presentation, when things go wrong. So I like this quote, he who makes no mistakes, makes no progress. I could have said he who makes no mistakes doesn't do anything. But this is really applicable to what we're doing. This is a learned skill, and there's going to be some heartache through it when you start from zero and you're going to try to approach the brick for the first time. There's going to be some challenges. I'm not going to sugarcoat anything for you all. This document is going to help you avoid as many of the big challenges you're going to face. But even if you follow the entire process, there could be something that may go wrong at the end. So what do you do then? And that is, first of all, you want to be proactive. Everything we talked about, reading the document, applying it to your QSM, having the open dialogue within your plant, having the nice culture to where the guys and gals in the field can go to the guys and gals in the bed and say, hey, something doesn't work here, and no one takes it personal. You're just trying to get a job done the best possible way for your customers. When you do that, you educate your customers, you make the samples early, and you document the entire process, then number one, your risk goes away, and number two, your quality goes way up. And I know the brick manufacturers and the form liner manufacturers will appreciate your professionalism in being proactive. And that goes a long way when you do, we do have to make some remedial changes or remedial actions. So what happens when you have to react to a problem? First thing is contact the brick manufacturer, form liner provider, your distributor ASAP. I've said this throughout the entire presentation, no matter where you're at in the process, if you're following the bouncing ball and you're staying on top of it, you'll probably uncover the problems before you get to the point to where you're in production. And a lot of things can get corrected before then. Document your concerns with photos and videos. Yep, it's a pain in the butt, and yep, you got to organize it, but when you have it, you can communicate it. A lot of times the problems don't happen, but at least you can work together to share the risk and get the job done. The top issues, fit between brick and form liner. So what do you do? Well, if you found out about that early when the brick showed up, you try to prevent it by sending brick to the form liner before they made the liner. Most often this doesn't happen, but sometimes it does. And when it does, you got to make the phone calls and there may be, you may have two truckloads of brick and it's not usable, and I've seen it. And I've seen brick manufacturers throw down with a saw and a grinder in a plant and solve problems fast. And I've seen others say, ship me the brick back, I'll send you new. So you just have to work with the brick folks and the form liner folks and figure out what's the best method to get the action corrected. Thin brick size conformance and thin brick color blend matching. That's kind of, kind of falls in the same ballgame. If it doesn't match, it doesn't match. You can, brick manufacturers are accustomed to staining brick. There's more projects than you'd ever dream of for you. They start putting brick on a high rise in New York City, they get to the third floor and the brick changes color. And now from floor three to four, floor 35 is all stained and you don't even know it. Staining brick is just a normal way of correcting a color problem. So don't shy away from that and they can blend and match and they can give a warranty. Delayed delivery is a big issue. You never know what's going to go wrong in a brick plant. I've heard multiple stories from different brick manufacturers who picked up the phone and called the producer and said, good news, brick is done, bad news is the color doesn't match. We're going to rerun it. I can either send you a bad brick that you're going to have to do something with and we're all going to do something with, or I can delay you three weeks and send you a good brick. Which do you want? So again, early communications on both sides can make a lot of problems go away, but those are the top issues. Now that you know those are the top issues, then hopefully you'll be able to manage around those going forward. I don't have any specific solutions for you today because those solutions are primarily project by project basis. I apologize for running over, but I'm here to answer any questions for anybody that wants to hang around. My only last statement is if you haven't downloaded the book, there's no excuse. It's free. And thanks to all those that participated in writing this document, I think it's well overdue. I think it's going to be a fabulous document, number one, to help reduce risks in plants, B, onboarding your plant personnel and C, educating your architects and also D, selling more thin brick and precast and sell more precast in general. So with that, Nicole, do you have any questions for me? Well, first, thank you, Randy, for a great and informative presentation. We are a little over, but we do have one question that came through and it's necessary that bricks are SSS. So WC of the concrete is not affected? Not necessarily. A lot of times people soak brick because that's kind of a standard in the brick industry is to soak brick. So the mortar, especially in hot climate, the mortar doesn't get sucked into the brick and then it loses its mortar content and it dries too soon and then it loses bond strength and there's cracking and stuff. There's a lot of reasons why people soak brick for precast, but the primarily reason they soak brick for precast is that it doesn't suck any water out of your mix. It's not necessary. I think it's just a question for your precast producer. Some people do it by, that's just the way they do it. And that's the way they do it. They found that it just works better for them. They get some of those horse troughs filled with water, unload the brick out of the boxes and put them in some sort of a wire basket and drop the wire basket in there every night and then pull it out and they don't find that it's a labor killer and they find they get a better product. But it's not necessary as far as a quality and performance perspective. Wonderful. Thank you, Randy. So then that is all the questions. So on behalf of PCI, I'd like to thank Randy again for a great presentation. If you do have any further questions about today's webinar, please email marketing at pci.org. Thank you again and have a great day.
Video Summary
The PCI webinar focused on "Recommended Practice for Embedded Clay, Thin Brick, and Precast Concrete," led by Randy Wilson, Director of Architectural Precast Systems at PCI. The presentation aimed to educate on PCI RP 152.25, which guides the selection and production process for precast components with embedded clay and thin brick.<br /><br />During the presentation, Randy emphasized the importance of understanding the manufacturing processes for thin brick, including the differences between residential and commercial brick, the manufacturing process's reliance on raw materials, and the importance of dimensional tolerances to ensure compatibility with form liners. The presentation recommended practices for selecting thin brick and form liners, including how to address brick size tolerances, anticipated waste, and the ordering process for bricks to minimize issues during production.<br /><br />The webinar also highlighted the significance of proactive steps such as proper sampling, ordering procedures, and pre-production planning to mitigate potential issues. Post-production practices, such as cleaning and inspecting precast panels and aligning coursing, were discussed to ensure quality. The presentation included practical advice on how to measure brick dimensions accurately using tools and provided an overview of solutions when issues arise, like staining mismatched bricks for color consistency.<br /><br />Randy concluded by urging participants to utilize the PCI's published guidelines to reduce risk, educate stakeholders, and foster better collaboration between precast producers and brick manufacturers. This will, in turn, enhance the quality and appeal of thin brick embedded in precast concrete structures.
Keywords
PCI webinar
embedded clay
thin brick
precast concrete
Randy Wilson
manufacturing processes
dimensional tolerances
pre-production planning
post-production practices
quality assurance
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